Gradometer



April 1945. PEER 7 2,374,124-

" GRADQMETER Filed Dec. 1; 1941 2 Sheets-Sheet 1 Z? 4 g A A 9 4 5 l l'/W 6 72 fl/2%ZZZ/?086'06 Q67 INVENTOR.

April 17, 1945. A. R. PEER I 2,374,124

GRADOME'IER Filed Dec.' 1. 1-941 2 Sheets-ShkZ INVENTOR.

Patented Apr. 17, 1945 U TE T TE PATE -.1?O F C GRADOMETER t a v":Arthnrltoscoe r ek;Berkei ism pgajwivafif Application December 1,1941, Serial No. 42 1',228

I v v I SGlaims. .-.(Cl 38--"89) My inventio'n relates to surveyinginstruments and has among its objects and advantages the provision of animproved g'radometerto facilitate the determination;- of the ascent anddescent of roads andthe-like.

' In the accompanying drawings:

Figure 1 is a side elevational view of an instrument in accordance withmy invention;

Figure 2 is a top plan view;

Figure 3 is an end view illustrating ment adjusted to an angle;

Figure 4 is a view similar to Figure 3 but illustrating the telescope ofthe instrument rotated ninety degrees from the position of Figure 3;

Figure 5 is a sectional view taken along the the instruline 5-5 ofFigure 1; and

Figure 6 is a sectional view taken along the I line 8-8 of Figure 2.

In the embodiment selected for illustration, I make use of a base plateI8 having a threaded member I2 for connection with the head of a tripod(not shown). Upon the plate I8 are mounted two supports I4 on which arerotatably mounted shafts I8 on a body I8 positioned bescale 88in-connection with either pointer. "Two pointers are "provided so as tofacilitate such reading from a position at either'side'of theinstrume'nt; A'splitcollar- 88 of the same type-as thecoll'ai' 22 i'ssecured to 'one Qffbh uprights '34, which collar clampinglyengagescne ofthe shafts 38 for securing the same against accidental turning. Atightening screw 82 corresponding to the tightening screw 28 is providedfor the split collar 88. v

To one of the shafts 38 is fixedly secured a needle 84 arranged to sweepacross a dial 88 on a dial plate 88. A glass window I8 encloses theneedle 84 in a housing 12 secured to one of'the uprights 34 by screwsI4. Dial 88 includes a zero position 18 with which the needle 84registers when the telescope 48 is positioned with its hori-- zontalhair line 18 in parallelism with the horizontal. Needle 84 may pivot toeither side of the zero position I8 through pivoting of the telescope 48and the body 48 as a unit about the axes of the shafts 38.

Spirit levers 88 are mounted on the plate I8, which levels are arrangedin right angular relaween the supports. Body I8 engages the sup 28tionship'to enable the plate I8 to be adjusted to a ports I4, as at 28,.to restrain the shafts I8 from relative endwise movement. A splitcollar 22 is mounted on one of the shafts I8with the arm 24 of thecollar fixedly secured to the adjacent support I4 by a screw 28. Atightening screw 28 is threaded into the arm 24 and passes looselythrough the arm 38 of the collar so that the shaft I8 passing throughthe collar may be frlctionally clamped to prevent accidental rotation ofthe body I8. Bearings 32 are mounted on the supports I4 for supportingthe respective shafts I8.

Body I8 includes two upstanding arms 84 prov vided with bearings 38rotatably supporting shafts 38 on a body 48 provided with a flat face 42constituting a rest for a disk 44 on a telescope 48. Disk 44 is providedwith a pin 48 rotatably journaled in a bore 58 in the body 48, the bore58 being arranged at right angles to the coaxial shafts 88. A nut 52 isthreaded on the pin 48 to hold the disk 44 in connected relationshipwith the body 48. However, he disk 44 may be rotated about the axis ofthe pin 48, as when the telescope 48 is turned.

An annular face 54 is provided on the body 48 of the same diameter asthe disk 44. A scale 58 is provided on the face 54 for coaction withpointers 58 secured at diametrically opposite points on the disk 44.Thus the degree of rotation of the telescope from one position toanother to providing a check for the needle 84 with respect to the zeroposition I8.

In operation, the instrument is set up at some point laterally of theroad or other formation to be measured for grade. The instrument is setso that the axis of the telescope intersects the grade linehorizontally. The point of intersection may. lie intermediate the endlimits of the grade. tated about the axes of the shafts 38 to; bring thehorizontal hairiline v18 in parallelism and registration with the gradeline. Such rotation of the telescope pivots theneedle 84 relatively tothe dial 88 for indicating the rate of ascent or descent of the gradeline. The dial 88 is callbrated to translate the angle in terms of rateof ascent or descent of the grade line, such as, for example, a tenpercent grade (that is, of ten feet to one hundred).

The telescope may be rotated about the axis of the pin 48 to move thehorizontal hair line 18 along the grade line. Such movement may be inmay b d ter ined by taking a reading o th either direction, dependingupon whether the When so positioned, the telescope 48 is roby applyingcurrent knowledge, readily adapt the.

same for use under various conditions of service.

I claim: 1. Agradometer comprising a support having two spaced andupright members, a body having shaft means mounted on said members forrotation about a first horizontal axis, said body having spaced andupstanding arms, a second body having second shaft means mounted on saidarms for rotation about a second horizontal axis at right angles to saidfirst horizontal axis, said second body having an opening arranged withits axis at right angles to and intersecting said 25 first and secondhorizontal axes, said second body having a first flat face lying atright angles to the axis of said opening, a telescope having a bodyfixed thereto provided with a second flat face lying on said first fiatface for supporting the telescope with its axis paralleling said firstand second flat faces, a pin fixed to the body on said telescoperotatably supported in said opening, and means threaded on said pin andengaging said second body to restrain the telescope from accidentalrotation.

2. The invention described in claim 1 wherein a. split collar is mountedon a part of said first mentioned shaft means and fixedly related to oneof said upright members, and threaded means for "clamping the collar tosaid part of said shaft means to restrain the first mentioned body fromaccidental rotation about said first horizontal 3. The inventiondescribed in claim 1 wherein one of said arms is provided with a fixedscale, and a pointer fixedly related to a part ofsaid second shaft meansfor coaction with said scale to indicate the degree ofrotation of thetelescope about said second horizontal axis.

ARTHUR Roscoe PEER;

